intrinsic factor

intrinsic factor
Biochem.
a glycoprotein, secreted by the gastric mucosa, that is involved in the intestinal absorption of vitamin B12.
[1925-30]

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      a glycoprotein (i.e., a complex compound containing both polysaccharide and protein components) with which vitamin B12 (cyanocobalamin (vitamin B12)) must combine to be absorbed by the gut. Intrinsic factor is secreted by parietal cells of the gastric glands in the stomach, where it binds with the vitamin. Thus bound, intrinsic factor protects vitamin B12 from digestion as it passes through the gastrointestinal tract and facilitates the vitamin's absorption in the ileum of the small intestine. Vitamin B12 is necessary for red blood cell maturation. A lack of intrinsic factor may result in inadequate absorption of the vitamin and cause pernicious anemia.

      The term intrinsic factor was coined in the late 1920s by the American physician William B. Castle, whose research into the cause of pernicious anemia indicated that two substances were involved: one that is produced in the body (intrinsic) and the other—an extrinsic factor, later identified as vitamin B12—that is supplied in the diet.

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Universalium. 2010.

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Look at other dictionaries:

  • intrinsic factor — n a substance produced by the normal gastrointestinal mucosa that facilitates absorption of vitamin B12 * * * a glycoprotein secreted in the stomach. The secretion of intrinsic factor is necessary for the absorption of vitamin B12; a failure of… …   Medical dictionary

  • intrinsic factor — intrinsic factor, in den Belegzellen der Magenschleimhaut gebildetes Glykoprotein, das mit ⇒ Cobalamin zu einem Komplex zusammentritt und so die Resorption dieses Vitamins im Dünndarm ermöglicht. Wird i. f. in unzureichendem Maß gebildet, kommt… …   Deutsch wörterbuch der biologie

  • intrinsic factor — n. a substance secreted by the stomach which permits the absorption of vitamin B12 in the intestines, thus preventing pernicious anemia …   English World dictionary

  • Intrinsic factor — protein Name = Gastric intrinsic factor caption = width = HGNCid = 4268 Symbol = GIF AltSymbols = EntrezGene = 2694 OMIM = 609342 RefSeq = NM 005142 UniProt = P27352 PDB = ECnumber = Chromosome = 11 Arm = q Band = 13 LocusSupplementaryData =… …   Wikipedia

  • Intrinsic Factor — Der Intrinsic Faktor ist ein Glykoprotein und dient der Aufnahme von Cobalamin (Vitamin B12, Extrinsic Factor) im terminalen Ileum (Hüftdarm). Inhaltsverzeichnis 1 Physiologische Bedeutung 2 Wirkungsweise 3 Krankheiten 4 Literatur …   Deutsch Wikipedia

  • intrinsic factor — a glycoprotein secreted in the stomach. The secretion of intrinsic factor is necessary for the absorption of vitamin B 12; a failure of secretion of intrinsic factor leads to a deficiency of the vitamin and the condition of pernicious anaemia …   The new mediacal dictionary

  • Intrinsic factor — In|trinsic factor [intrịnßik fạ̈kter; aus gleichbed. engl. intrinsic factor (eigtl. = von innen wirkender Faktor)] m; [s], s: Bezeichnung für ein normalerweise in den Fundusdrüsen des Magens u. im oberen Abschnitt des Zwölffingerdarms… …   Das Wörterbuch medizinischer Fachausdrücke

  • Intrinsic Factor — In|trin|sic Fac|tor [ fæktə] der; [s], s <aus gleichbed. engl. intrinsic factor, eigtl. »von innen wirkender Faktor«> Bez. für ein in den ↑Fundusdrüsen des Magens u. im oberen Abschnitt des Zwölffingerdarms produziertes Enzym, das zusammen… …   Das große Fremdwörterbuch

  • intrinsic factor — noun a substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12 lack of intrinsic factor can result in pernicious anemia • Hypernyms: ↑factor …   Useful english dictionary

  • intrinsic factor — A mucoprotein normally secreted by the epithelium of the stomach and that binds vitamin B12; the intrinsic factor/B12 complex is selectively absorbed by the distal ileum, though only the vitamin is taken into the cell …   Dictionary of molecular biology

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